Experiment and application of new material for grouting of gangue based aquifer

Coal mining in the aquifer with high bearing pressure often needs to carry out the transformation to the strong aquifer. Tens of thousands of tons of grouting material are used because of the large scale of aquifer. Based on the modification mechanism of inorganic composite,a new type of inorganic grouting material is developed by using sol- id waste in mine and thermal power plant. The optimum mixture ratio of new material system is obtained by the labora- tory test. The flexural strength,compressive strength,permeability coefficient of different composi-tions are tested,com- bining with the grouting engineering to select ratio. The microscopic structural performance of grouting stone body is tested by the micro analysis means of XRD and SEM. The mechanical properties,economic factors and environmental benefits are compared,and the applicability of the new materials and conventional grouting materials is compared. The results show that the cement content is 35% ,the early strength and later strength of the new grouting material are high- er than that of the cement clay slurry at the same time when the cement content is 40% . The cement content is 30% , the clay content is 10% ,the coal gangue content is 60% ,with appropriate content water reducing agent and accelera- tor. As for composite material stone body (28 d), the com-pression strength is 3． 4 MPa, the flexural strength is 1.7 MPa,and the permeability coefficient is 1． 794×10-7 m / s. The results meet the requirements of aquifer grouting reconstruction,which is expected to offer some reference to similar projects.